SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b13779b67e7035b9dfd151a8deab9ea00dafb970bf47f9085cfe5d6aaef632be' 
  AND token = '9pBzECq9n7RX3ThmUHWGXYFTnpUv8+ksG0u3OPUrWVk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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