SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e3d53170abf06dd73520057e1e3fc853d3e386783f4736adb4d26e4dbb027e28' 
  AND token = 'I1y4Q0cTihSMB4JfU2UcE30clfSS3GWRRnCTFtGBHC0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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