SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8d37960c96514c50e0d43b909b72f8c3e0117955f627767b3c20137ae7f81bdc' 
  AND token = 'FxwW6Om70yL5gKAocBZGe56mJfVgfG+qbiaJNsu/d8M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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