SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bf86274f35fc018364d2d2daf8cf80777fc975692175179f6879b3e348334235' 
  AND token = 'JxaDCmQNgIYQAVr+3jM6x+R1gBPy6ZxdFys/hKBUa/A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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