SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fbfc0c97fc5ac3b515ec551fb730525fc7a7e2be82f0f47b7fc48d7cee16a825' 
  AND token = 'iHl3KXLy9fMMoQYZlBwMCuNEMyeqUqAgB3Os4vsFOUo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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