SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '38e0f99505e2e382a8af1614df2fdf17cd03209c37541128cbc8b2fe1c6470f5' 
  AND token = 'BVI0VhiKP+M4YZlZwPse25BQ4TLoqjmrhUdWaoN1zGE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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