SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5e88c6b4274d9dce80b3a1c4eb3ed51729b1af559e2b2d5ea92fe458e38c6f73' 
  AND token = 'FmdbfKFGiekMHNjX6tzq0G3Six/BlL6h+LDphnJxOG4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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