SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06b2e99d627098243fefb6b203d7f546901e4555addc3fe277e00be2f496b50a' 
  AND token = 'S9CyCsHkRRV3CbV2LnwJ/h3ZOI+07t5ktyeq/AZIXxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}