SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af48083ac89723d87ae8d114c3fb4769c72cf5cc3f4dd090fdba96856c39cf84' 
  AND token = 'SN9isOSaYj2C1t6JmhWcxekmYowv4Y1u2C6c81y9U68=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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