SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33c32564981e10793a063ab753fc16a2971eefb17f8628e0969805faacd0afbb' 
  AND token = 'XJEjAvK9LzQ+BsAcFSK7P14nWP+8HF3WzB9uuFvPVMM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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