SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09aa3dad060a8463871fc18a721f4aa0fd74cd65f0816fd90dd4b286fba9f121' 
  AND token = 'm+/6yRTUgOPkxYhljM+HsPbNRGaeuGAwHhKYjK+2wNI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}