SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3a217b4d74b1f086024f8af4689e8fa55f49b26fae6473537850281fa0882878' 
  AND token = 'FpMqs8OF1hvZjIJkcrQGbuqVFKhHPIh25AOrHw8fL9Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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