SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30a09e81df681c1c425b4793d1e2e95b947df5311bf95d76382e6a5c7cdadc2f' 
  AND token = 'J+rFj4+BS5TFGIXRxbrKnIkxla+6sNL6bAtWI4YcI9w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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