SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a9a227ec73f2a873c8ab7eb891fa327abe954eb44b2edcc0e9116b770db61dc' 
  AND token = 'mkW8LgMf1bGVS3067FOfDY+DcPDwYC6rQph5EnEOL34=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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