SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'eceaee99620babc9c361d7d9021e0adaed531d3835b5d33e40702d8a276579d5' 
  AND token = 'vwZn9paLmSCogEJwSw7OTTmVujPSbB+kpqzpz1hXqMo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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