SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63a99325535c73fb319fb9ebbc55c5803d4fbab73ac9c2f34ea358e606b93e48' 
  AND token = 'z9gEzcYi9VQkQ2ZYr2pRQM360/oeZBZVOi6xyB9wDLI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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