SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd19641941ef1c564c7608e8710bddb8795c9d3b3023933681926614e8a0ed373' 
  AND token = 'VFrjkbgG130w0FWeLuAqoJ9PBnfKia3AlemaJwCySjA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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