SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '2c1270087c90daad1eb82ebcd6f44274ed092f396c136184a3b9fdfa6fd411bb' 
  AND token = 'JiPk7khNZ/yEuJe+FsDMPIm0bqNCyIlqhvO39f2cyG0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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