Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '0b67da17c51fe8caf4e073a6713b3e3434767380155b73060a9cfd4e86bd7b28' 
  AND token = 'p4Ij6W3b5P1EM1KiS9E0QsBIYdvHB8LrKPPGAguI2cI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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