SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6b05b46d034b735ce1e67acc8feddf7659b4a03eec7a9954c334e6eb9261a9b7' 
  AND token = 'QmMqqmajhvVHZjYJJjGWR8prbFEewCMemBfZv8/YCkI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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