SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f9dd4f26c6fd2b99768bd23777f2535302e12fba15980e93f0c35d6dc12c820e' 
  AND token = 'KqWpZrk9tvwHsWJ3+qr1mkrzKKbtBd1eHm63NYd5j0g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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