SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1adfb98d2cbfb188f29d5f2143cbda802091bcd090cf6e227245364b34b04f2' 
  AND token = 'ALV8XsK7gTTLDAhl7acaz1PIG1DB5iqODO3w4iXQJ4w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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