SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b4ce608eaa0a26e8d8e1920ea32c604f0c355764504081f28336237095dcc787' 
  AND token = 'yxZUWHr1UFpYAf+WZgwnchJ8tqvHpLcbDymnuwFUQQ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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