SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '26ab6b2e600d4fc76f752b0514afbdb183a84d6c836a321e59384f3fab011bb2' 
  AND token = 'RCEyuXGIwgreN3Y6CM4yKS+jsEDGkvbSVcdFdUTpKBQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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