SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf269b96793aea927224115b97d43b518631d52cc468658592dd9fb76558693e' 
  AND token = 'pGZvC2w0boWvM5/jrxPl85q3xyU4o7LaaBWTVUZ+bA4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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