SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c2a509f9e327e911c80c7533f528e744bd99e2a7638cc49a8485fe306ab779d' 
  AND token = '+SoewNVbHrXj5uxMGLf7tukivSfiYQouq/DxwIuXmh0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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