SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fa89945e89dd5efcdefe1d02ddb7b29b77e348e507931c7eb79fc2738c815fb' 
  AND token = '85UVVoX0a0UyB+NIU60q+0oyexdVQkM6mFzrOZdzVsw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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