SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd264852a66e2d3922ffda668258ef67f4fb86697b77de83bf9988b64fb06ff2a' 
  AND token = 'MAjq8QnA1hNyzYBt0V+UVA3GrHKwbuXUvKiLBo64xr8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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