SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41e598961d0422389d5ddc06c276854293a84160e16f5a7e88d32b6c1a7ae5c7' 
  AND token = 'BcVKLj8euXHgCQfW2Z4humeq7MZqK6hNSHpax7DH+W8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}