SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dbf2a4431f8b4f21f55f82d73d601430dc725b80a204912c4a76b542ce719039' 
  AND token = 'TKVUo/sDv34DvMT7OGakfrFZXUzGAAEqR2jXJrQTugU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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