SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee5c745ca31798346de0d9a3e496531d9e73f38ba43d2f15feca4eec6e8cbe88' 
  AND token = 'I0UTbv5lc/BSVIOFYJKlyKTNhZR8aNniIVmRXzKBCSA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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