SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e9562e07a54d65ad4525f9a25c0a7aa88ac8c925368a5ea9f8ad6aa2f1410cd' 
  AND token = 'J2cpyiitA5IGuWgvHNcXQ02wxOoWymB33BFYp8RmrSY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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