SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc3e30307eacd77b681039f1f49ae4cce0fa07698eed3f500d51c48845199cd2' 
  AND token = 'AUgsD5yCiUIBNe0GbUKGafjPzXT4R2mZ5qL9NvGYKkM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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