SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d880e893d12fe679651420ef5db974bb6b8f7175ba8cbc71e4bbcbe5d5c2cb3' 
  AND token = 'uTwdep9j5CzJZa6Zzh3TO5/EuwvBDasc/sOxBMWk7do=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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