SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7f642c33de7b2c57f0dfb190c74d3a410c2a510ff69bde9789e252373c7ca985' 
  AND token = '6GpCGc2mj+hh0oPBlXjr1XiXoh9jo5V/XGZOXFt7EV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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