SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ca1d5ed3f7852d9a03f2306ef8e76fcce37be425620953d4a29149f6468f4877' 
  AND token = 'k+EUvIQfZZCvYgVRXIfd3tP4v/dEwISYvuTX/6O0VPY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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