SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d6962ecd8a2fa7eb85ad73c340e1ec29887c1e1212a819a2cd3129fcbcf341a' 
  AND token = 'kTYEeOKkLD6OlttJmRzzW9VJtwscSx/ZMgF0ljxbGKE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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