SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '166a3442e8d5ff513c63410878958012b1d50f459ba095331bdef5aa73e1ecfe' 
  AND token = 'NgcmZvhzvDsdSCpCbGSr7YbmMaqxj2Ni/DMl0DYaKCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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