SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1370c27baab1f8134071276b96e7a64cc661ea776a8f27dfe16b026cad7283e5' 
  AND token = 'ZxqWeCKZAOiaGE7GRAr9IQoWUryXSvco8WeAWPGuzVQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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