SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7914ef6795f31d34e0a7fb0d770c44ca3246f60a8d2df76452cf20d43a2a6eb8' 
  AND token = 'exgp1+5VFLDJ/QJL0tOvs+cpvxJOJazK8mlPAcKs+uA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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