SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '56273ed3cee65e146ad3df22d5b0b613c5cea42917e276f753a90ec3ec46ab56' 
  AND token = '4uneMlrVeVh/45+H+K64yoV0h4XLtWIaPUCZwot0enw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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