SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '466580c0057865cba91d594c70deceb6d32937667983b1e7b48ee3000feda77f' 
  AND token = 'rpC7IFeFXa8o/XjocVK4t0qv3FJLuaZ3wbayFWvkON4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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