SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dde88e0645773dd9ca1cc5217f1a4334f94028851a75e1469b0edaff84e73381' 
  AND token = 'UPXGxJblCgiUM5ZTdDwN1hFw1aPRCZzKr0ppnRbvmZk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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