SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45d101bdacc69c92f9e0319e24775d120357521c9bf5ceb114561ec18e70715f' 
  AND token = 'yeSHVszOYz1BM+uZNxhM9WxL0jNPdElRb2JwGcNcdHY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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