SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'e4a0332b6229d463e4e91e526ec740534f0a4cfbe0fa1da7169022a6242561fa' 
  AND token = 'IAICEszcHLnI+O6w9yUyjRh1jRj5/ye5ja5bS4YFLzo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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