SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bcf3beae58740dffc3bd6335212928207cef016ef3bea3ddc765367ab931b581' 
  AND token = 'daSUZlwHPvZqq9JvM/R9xo35IyoDRbZfndUTRHPhopA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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