SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f8ee7d7b4c5fc7d94efae1127327209aa0f41ea45b41352eabeea366991ef95' 
  AND token = 'zxTrL9W5E/EVrQ7ssk8HVkIP40cDWKFjIqoKEzggoa0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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