SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be567ef79d3d927e531ef6f1890b4159b34e724837630cbae828e63386c1cb58' 
  AND token = 'c5FYNQjICPU8nac9MKsDArkMQnsI6PBXRTdZ2Er6T+M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00075

JSON explain

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