SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '602982c2057ce4024e1622a850184d80461f33e805bf67078a47dd8b939f6863' 
  AND token = 'wDwc43qp0hfW7CxHRR3X5g3vNgjezqmikMHuLKWhXLg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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