SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'af67a9de861619d1dd92a577304a3146e9d1559ffc2f9e465dcd2856543b832a' 
  AND token = 'A3qlw5NB0+yWXg1FmHGeXV8gdAjEvs9OHJBIbCF+WQ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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