SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41582eecb1a741051a97c1575f27f2ad65bcb4c30e3af24a0a60fa9199d6e312' 
  AND token = 'WHuYfKFVOx9sNhuGtS9jSZ0ETrLNUWqW7vzSCrf6rzs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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