SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45e92ffe9db6403284afd930f48715bd62c3c3b897efbfacb51c2773a1f6d015' 
  AND token = 'KqCoKIHxAQF7x+YtHB8iozOEVPzOC61NGwlC39M8g+A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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