SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '39a05a13a942c553b27550e6275a9fe84773dcdd94971ce583111d0a44cb467d' 
  AND token = 'iW/TY4CNnUOrQ8XIhpyfWQjy+PMfgRu/od0fdTA0LdU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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