SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6fdf7661b79215479ac7ddf530801b93cf0b95bff793dcbcddbc454ff226fd5e' 
  AND token = 'EUb4izfLr/suDshC5UKS9kWx3hiC36kL/AoJBzQBc/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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