SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '935462dc7b67b19d0ad714fb243a5606a33ac88fd39d2f30f47ddfe49a612ad9' 
  AND token = 'iNs23qKOApNtgGLxnIVxfJXCNEG0aRPWiEdC3jg08RQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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