SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3aa7926929cd1e4b408ef237a42e72292876956a9fa6b28aa7483e4369aef184' 
  AND token = 'q0W7a66P+sFYReXHKmMBu+fKUh0MjdcMXioXjwzVRh0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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