SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f62f6253f0aebe6f9db9e45aef396a8cea5419685e3d39f06dc3ef5b67f37d6' 
  AND token = '9K5nXJ/PdP6c+DfpM7exNTjZ7m+K78VpRzG2mRgHqhQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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