SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abecf71b194ee0d86f79d8829050d31c704ee878f95d93a1d342bee79573b5fe' 
  AND token = 'uW8hfGbMgTmDC7dpm4EnpCayaKyd2SMzUFbnA/UOEJQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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