SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f86a4a860ae83bc626cddf4b473faa9261132feb4729f28f628161ff0d6935b0' 
  AND token = 'tGFHaWekqExACYDDOTAMM4w7CeWEk7s39l2fHH0aRd8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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