SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '49c38531d7019da9709ecb4102a215ed39ccf557e7e82022c551ffe47ddfb306' 
  AND token = 'lqqGrYeG3LxYVveE3S1JhBsopbll3jKNII4pmrnOkOM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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