SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48deaa561cb16562b3351fe2ca99c6dfd853b34add8f76d9c0cde746ef24732e' 
  AND token = 'fOrXaxG1waImcn7qbgknHquq4FOhUKvseGGLFzAl77g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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